Laboratoire LG2A

Laboratoire de Glycochimie, des Antimicrobiens
et des Agroressources UMR 7378 CNRS

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Actualités et Publications

Phenylpropanoid profiling reveals a class of hydroxycinnamoyl glucaric acid conjugates in Isatis tinctoria leaves,

Nguyen, T.-K.-O.; Jamali, A.; Grand, E.; Morreel, K.; Marcelo, P.; Gontier, E.; Dauwe, R.

Phytochemistry 2017, 144, 127-140.

The brassicaceous herb, Isatis tinctoria, is an ancient medicinal plant whose rosette leaf extracts have anti-inflammatory and anti-allergic activity. Brassicaceae are known to accumulate a variety of phenylpropanoids in their rosette leaves acting as antioxidants and a UV-B shield, and these compounds often have pharmacological potential. Nevertheless, knowledge about the phenylpropanoid content of I. tinctoria leaves remains limited to the characterization of a number of flavonoids. In this research, we profiled the methanol extracts of I. tinctoria fresh leaf extracts by liquid chromatography – mass spectrometry (LC-MS) and focused on the phenylpropanoid derivatives. We report the structural characterization of 99 compounds including 18 flavonoids, 21 mono- or oligolignols, 2 benzenoids, and a wide spectrum of 58 hydroxycinnamic acid esters. Besides the sinapate esters of malate, glucose and gentiobiose, which are typical of brassicaceous plants, these conjugates comprised a large variety of glucaric acid esters that have not previously been reported in plants. Feeding with 13C6-glucaric acid showed that glucaric acid is an acyl acceptor of an as yet unknown acyltransferase activity in I. tinctoria rosette leaves. The large amount of hydroxycinnamic acid derivatives changes radically our view of the woad metabolite profile and potentially contributes to the pharmacological activity of I. tinctoria leaf extracts.

Applications of Glycosaminoglycans in the Medical, Veterinary, Pharmaceutical, and Cosmetic Fields,

Kovensky, J.; Grand, E.; Uhrig, M. L.

Industrial Applications of Renewable Biomass Products: Past, Present and Future 2017, 135-164.

Glycosaminoglycans (GAGs) are complex polysaccharides ubiquitously present in the extracellular matrix of mammalian tissues, where they constitute the gelatinous material responsible for maintaining the cells together, in an intimate association with a variety of proteins. Although their structures are not strictly regular, they are composed of a repeating unit of a hexosamine-containing disaccharide. Most of them possess uronic acid residues, and with the exception of hyaluronic acid, they also carry sulfate groups. As a consequence of their high negative charge, they have an extraordinary capacity to absorb water. GAGs participate in many relevant biological processes by interaction with a plethora of proteins, and thus, a large number of applications in different fields have been conceived for GAGs and their derivatives.

The effect of room temperature ionic liquids on the selective biocatalytic hydrolysis of chitin via sequential or simultaneous strategies,

Husson, E.; Hadad, C.; Huet, G.; Laclef, S.; Lesur, D.; Lambertyn, V.; Jamali, A.; Gottis, S.; Sarazin, C.; Nguyen Van Nhien, A.

Green Chem. 2017, 19, 4122-4131.

An efficient conversion of chitin, the second most abundant renewable polymer on the Earth, into N-acetylglucosamine and N,N[prime or minute]-diacetylchitobiose, using room temperature ionic liquids (RTILs) and commercially available chitinases is described for the first time. The sequential strategy consists of the use of RTILs to pretreat chitin under mild conditions as a first step before enzymatic hydrolysis. [C2mim][OAc] (1-ethyl-3-methyl imidazolium) pretreatment provides an efficient production of N-acetylglucosamine (185.0 +/- 4.0 mg per g chitin) or N,N[prime or minute]-diacetylchitobiose (667.60 +/- 20.71 mg per g chitin) catalyzed by chitinase from Trichoderma viride or Streptomyces griseus, respectively. A thorough investigation of the structural changes of chitin induced by RTIL pretreatment suggested an increase in enzymes' accessibility to the chitin substrate. Alternatively, a one-pot enzymatic hydrolysis of chitin in [C2mim][OAc]-aqueous medium constitutes a promising simultaneous route to selectively generate N-acetylglucosamine or N,N[prime or minute]-diacetylchitobiose by decreasing the required [C2mim][OAc] amount and the number of steps. Finally, the combination of the two chitinases from T. viride and S. griseus was shown to be very relevant to considerably increase the production of N-acetylglucosamine up to 760.0 +/- 0.1 mg per g chitin.

La chimie en Région Hauts-de-France : Chimie, biologie et santé,

Stéphane Lebrun, V. A., Philippe Amouyel, Christophe Biot, Véronique Bonnet, Benoit Deprez, Pierre André Gilormini, Cédric Lion, Oleg Melnyk, Patricia Melnyk et Jérôme Vicogne

Actualité Chimique 2017, 46-51.

Cet article présente un tour d’horizon de quelques-unes des thématiques de recherche développées en région Hauts-de-France dans les domaines de la chimie, de la biologie et de la santé.

La chimie en Région Hauts-de-France : Chimie de la biomasse,

Philippe Zinck, J.-M. A., Rémi Beaulieu, Fanny Bonnet, Thierry Delaunay, Franck Dumeignil, Cédric Epoune Lingome, Audrey Favrelle, Régis Gauvin, Frédéric Hapiot, Nicolas Jacquel, José Kovensky, Raphaël Lebeuf, Christophe Len, Éric Monflier, Véronique Nardello-Rataj, Jesus F. Ontiveros, Sébastien Paul, René Saint-Loup, Mathieu Sauthier, Isabelle Suisse, Marc Visseaux, Anne Wadouachi et Patrice Woisel

Actualité Chimique 2017, 40-45.

Cet article présente un tour d’horizon de quelques-unes des thématiques de recherche développées en région Hauts-de-France dans les domaines de la chimie de la biomasse.

Decreasing redox voltage of terephthalate-based electrode material for Li-ion battery using substituent effect,

Lakraychi, A. E.; Dolhem, F.; Djedaïni-Pilard, F.; Thiam, A.; Frayret, C.; Becuwe, M.

J. Power Sources 2017, 359, 198-204.

The preparation and assessment versus lithium of a functionalized terephthalate-based as a potential new negative electrode material for Li-ion battery is presented. Inspired from molecular modelling, a decrease in redox potential is achieved through the symmetrical adjunction of electron-donating fragments (–CH3) on the aromatic ring. While the electrochemical activity of this organic material was maximized when used as nanocomposite and without any binder, the potential is furthermore lowered by 110 mV upon functionalization, consistently with predicted value gained from DFT calculations.

Oligogalacturonic Acid Inhibits Vascular Calcification by Two Mechanisms,

Hodroge, A.; Trécherel, E.; Cornu, M.; Darwiche, W.; Mansour, A.; Ait-Mohand, K.; Verissimo, T.; Gomila, C.; Schembri, C.; Da Nascimento, S.; Elboutachfaiti, R.; Boullier, A.; Lorne, E.; Courtois, J.; Petit, E.; Toumieux, S.; Kovensky, J.; Sonnet, P.; Massy, Z. A.; Kamel, S.; Rossi, C.; Ausseil, J.

Inhibition of Vascular Smooth Muscle Cell Osteogenic Conversion and Interaction With Collagen 2017.

Objective—Cardiovascular diseases constitute the leading cause of mortality worldwide. Calcification of the vessel wall is associated with cardiovascular morbidity and mortality in patients having many diseases, including diabetes mellitus, atherosclerosis, and chronic kidney disease. Vascular calcification is actively regulated by inductive and inhibitory mechanisms (including vascular smooth muscle cell adaptation) and results from an active osteogenic process. During the calcification process, extracellular vesicles (also known as matrix vesicles) released by vascular smooth muscle cells interact with type I collagen and then act as nucleating foci for calcium crystallization. Our primary objective was to identify new, natural molecules that inhibit the vascular calcification process.Approach and Results—We have found that oligogalacturonic acids (obtained by the acid hydrolysis of polygalacturonic acid) reduce in vitro inorganic phosphate–induced calcification of vascular smooth muscle cells by 80% and inorganic phosphate–induced calcification of isolated rat aortic rings by 50%. A specific oligogalacturonic acid with a degree of polymerization of 8 was found to inhibit the expression of osteogenic markers and, thus, prevent the conversion of vascular smooth muscle cells into osteoblast-like cells. We also evidenced in biochemical and immunofluorescence assays a direct interaction between matrix vesicles and COL1 via the GFOGER sequence thought to be involved in interactions with several pairs of integrins.Conclusions—Degree of polymerization of 8 inhibits vascular calcification development mainly by inhibition of osteogenic marker expression but also partly by masking the GFOGER sequence—thereby, preventing matrix vesicles from binding to COL1.

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